| In order to improve the effect of disposal of cellulosic ethanol waste water of straw,the project selected six kinds of Dongbei local white-rot fungi to dispose by degradation the lignin in cellulosic ethanol waste water of 2%straw.The experiment adopted orthogonal test to optimize the screened efficient degradation fungi in producing laccase culture medium.The laccase production of six white rot fungi was determined.The laccase activity of Pycnoporus sanguineus peaked at 10 days and the laccase activity was 116.43 U/mL.In the 16th day,Polyporellus picipes reached the peak of laccase activity,and its laccase activity was 120.89 U/mL.The Pleurotus ostreatus reached the peak of enzyme activity on the 8th day,and its laccase activity was 63.52 U/mL.The laccase activity of Coriolus uersicolor,Bjerkandera fumosa and Ganoderma lucidum was low,reaching the peak of enzyme activity on the 20th,12th and 18th days respectively,and the laccase activity was 3.78,2.47,1.66 U/mL,respectively.The results showed that the six kinds of white-rot fungi are Polyporellus picipes>Pycnoporus sanguineus>Pleurotus ostreatus>Coriolus uersicolor>Bjerkandera fumosa>Ganoderma lucidum in the sequence of enzyme activity;Six kinds of white rot fungi were used to degrade lignin in cellulosic ethanol wastewater.the initial concentration of Pycnoporus sanguineus,Pleurotus ostreatus,Coriolus uersicolor,Polyporellus picipes,Ganoderma lucidum and Bjerkandera fumosa at the 0th day were 640.9-716.6mg/L,the concentration of lignin at the 14th day were 434.0,411.2,441.8,441.7,533.3 and 503.5mg/L respectively,the removal rate for lignin were 37.1%,37%,31.8%,31.7%,25.6%and 21.4%respectively.And the degradation trend of lignin was to be stable at the 12th,12th,4th,4th,2nd,6th day respectively.It can be seen that the white-rot fungi with the best degradation effect is Pycnoporus sanguineus;Pycnoporus sanguineus produces laccase culture medium:the best origin of carbon is saw powder with mass concentration of 35g/L,the best nitrogen source is peptone with mass concentration of 4g/L,the best pH is 5.Wherein Pycnoporus sanguineus more adapted to grow in a weakly acidic environment bias,than inorganic nitrogen source organic nitrogen species is more conducive to producing laccase.the range analysis showed that the influence sequence of various factors on Pycnoporus sanguineus in producing laccase is source of carbon>nitrogen source>pH>concentration of nitrogen source>concentration of carbon source;The optimal medium was used to degrade the COD in 2%of the cellulosic ethanol wastewater.The initial degradation rate of COD on the 0th-4th day was faster,and the degradation rate of lignin on the 4th day reached 45.3%.With the increase of degradation time,the degradation of COD by Pycnoporus sanguineus was slowed down on the 4th to 8th day,and the COD degradation rate did not change significantly.The removal effect of COD was not significantly improved,and the removal rate was always maintained between 46.9%and 47.6%.On the 8th day,the greatest COD removal effect was achieved,COD decreased from 1928.8 mg/L to 1010.8 mg/L,and the removal rate reached 47.6%.The results show that Pycnoporus sanguineus can degrade COD in straw cellulose ethanol wastewater,but its degradation effect is not ideal,and the average efficiency is about 50%.The pH value of white rot fungi degrading 2%cellulosic ethanol was measured.The initial pH value of the culture was 4.9-5.9.The initial pH value of white rot fungi was 4.9-5.9.With the prolongation of culture time,the pH value showed an increasing trend.The pH of the wastewater added on the 18th day was 8.25.The pH of undosed wastewater reached 7.9.The overall trend of pH is increasing.The pH of the added wastewater is compared with the pH of undosed wastewater.When the straw cellulose ethanol wastewater is added on the 9th day,the pH is decreased.Because the straw cellulose ethanol wastewater is acidic,wastewater is added to the wastewater.Afterwards,the pH drops.Afterwards,the pH slowly rises.The research provides source of fungi for disposal of cellulosic ethanol waste water of straw by means of bioanalysis,and provides scientific basis for further application and research in the future... |
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